The Merriam-Webster Book of Synonyms (Apr, 1948)

Isn’t this called a thesaurus?

The Merriam-Webster Book of Synonyms
helps you use the right word in the right place
WEBSTER’S DICTIONARY OF SYNONYMS clarifies distinctions between Synonyms, giving their Antonyms and Analogous and Contrasted Words, explains differences in their shades of meaning, and illustrates usage. Prepared by the famous Merriam-Webster editorial staff. Alphabetical listing and cross-indexing of every entry. Over 900 pages, thumb index, $5.00. At your bookdealer, or from the publishers. G. & C. Merriam Co., 745 Federal St., Springfield 2, Mass.